Much research has also been conducted on everolimus and other mTOR inhibitors as targeted therapy for use in a number of cancers. It is marketed by Novartis under the tradenames Zortress (USA) and Certican (Europe and other countries) in transplantation medicine, and Afinitor in oncology. Everolimus also available with Biocon with the brand name of Evertor.
Female fox and gray squirrels that are at least two years old have two litters per year, younger females have only one litter per year. Average litter size is two to four (southern flying squirrels may have litters of up to seven young), with young weaned around eight weeks of age.
Although baby squirrels have been recorded in almost every month of the year, these two litters, early spring and late summer, are the norm. Typically the early spring babies have the highest survival rate, especially in areas where it snows, since a small squirrel has to expend more energy than a large one to stay warm and find food.